import java.util.Scanner;
public class Elaina_10_5_ti2
{
    public static char toLowerCase(int l)
    {
        return (char)(l+32);
    }
    public static void main(String[] args)
    {
        Scanner sc = new Scanner(System.in);
        char l = sc.next().charAt(0);
        System.out.println(toLowerCase((int)l));
    }
}
